Which Sennheiser headphones are best? 2026 Hong Kong HD Series Buying Guide
- HD 600 official specifications: 300Ω, 12Hz–40,500Hz, 97dB(1V), 260g, open-back, made in Ireland
- HD 660S2 official specifications: 300Ω, 8Hz–41,500Hz, 104dB(1kHz,1Vrms), 38mm drivers, 260g
- Our store has documented stock availability for all 7 open-back models in the HD series + 1 closed-back model (HD 620S), with prices starting from HK$1,280
- The entire Sennheiser range consists of parallel imports and comes with a one-year store warranty
| 1 HK$ = | S$ SGD | A$ AUD | £ GBP | US$ USD |
|---|---|---|---|---|
| Reference exchange rate | S$0.16332 | A$0.18128 | £0.09565 | US$0.12748 |
30-second answer: choose directly by use case
For the same brand, the HD series ranges from HK$1,280 to HK$8,299; the biggest difference isn't "how expensive it is," butwhether you have a headphone amp capable of driving it. The table below is organized by use case, and the prices are the current lowest-configuration prices in our store.
Conclusion:If you haven't bought a headphone amp, don't start with HD 600—It's not that it can't be driven loud; it's that you can drive it loud but not properly, leading you to mistakenly think the headphones aren't worth it.
What makes 300Ω difficult to drive
300Ω is a high impedance, so what it needs isvoltage swing, not simply “more wattage.” The output voltage of a phone or computer headphone jack is limited, so the usual result is sufficient volume but compressed dynamics, loose bass, and a flat soundstage.
The official data provides a useful comparison: HD 600 has a sensitivity of 97dB (1V), while HD 660S2 is 104dB (1kHz, 1Vrms).HD 600 is harder to get to a sufficient volume,HD 660S2 is easier to drive at the same impedance, but both are still recommended to be paired with a dedicated headphone amp.
Practical threshold: a desktop headphone amp with a 6.3mm output and a stated ability to drive 300Ω, or a USB-C-powered DAC/headphone amp combo, can improve what you hear more than changing headphones.
How to tell the three HD 600 / 650 / 660S2 brothers apart
All three are open-back, 300Ω, and 260g; the differences lie in their tuning and bass extension.
How to choose:For “hearing accurately,” choose HD 600; for “comfortable listening,” choose HD 650; for fuller bass between the two, choose HD 660S2. HD 600 is officially described as the reference standard for over 20 years. It is not new technology, but it is the most neutral; HD 660S2 lowers the diaphragm resonance frequency to 70Hz and doubles the bass sound pressure, with the difference most noticeable when listening to modern pop, electronic music, and film soundtracks.
Open-back or closed-back: add the HD 620S
The advantages of open-back headphones are a natural soundstage and no internal chamber resonance; the trade-off issound leakage and virtually no isolation。If you share a space with others, or need to capture audio from the adjacent room while recording, you should not buy HD 600／650／660S2.
Sealed alternative: HD 620S (42mm drivers, 150Ω,HK$2,099). Closed-back headphones usually have a slightly narrower soundstage, but in return they offer no sound leakage and more controlled bass, making them more practical for offices and dorms.
Don’t want to buy a headphone amp: HD 505 / 550 / 560S / 599
These four models are source-friendly, with lower impedance and reasonable performance when connected directly to a computer or a small dongle DAC.
- HD 560S HK$1,280—Neutral and analytical, and the entry-level monitoring headphone most often recommended; the first choice for hearing details and practicing mixing.
- HD 505 HK$1,480—120Ω, 12Hz–38.5kHz, suitable for both music and gaming.
- HD 550 HK$1,399—6Hz–39.5kHz, with a more versatile tuning.
- HD 599 HK$1,499—50Ω, the easiest to drive, with a relaxed fit.
If you use your phone or laptop directly 90% of the time, this section is your answer; rather than buying the HD 600 and then complaining that it is “not loud enough,” get the HD 560S with a slightly better DAC.
Bluetooth options: MOMENTUM 4 / ACCENTUM / MTW4
If commuting, working in the office, and taking calls are your main use cases, you shouldn’t buy open-back wired headphones. Our store offers three options:
The price difference mainly comes down to noise-cancellation performance, battery life, and call microphone pickup—not “sound quality tier.” If you want wired audiophile sound, Bluetooth is always a different path.
In-ear monitors: IE 600 / IE 900
If you need isolation and portability, in-ear monitors are more practical than open-back over-ear headphones.IE 600 (HK$3,899)It uses a German 3D-printed housing and a single dynamic driver with a pressure chamber, giving it a monitoring-oriented sound;IE 900 (HK$7,999)It uses an XWB driver, offers 5Hz–48kHz response, and is made in Germany, placing it in the flagship class. Both are sensitive to the source, so driving them directly from a phone would be a waste.
Things to Note About Parallel Import Warranty Service
Our Sennheiser headphones areparallel imports with a one-year store warranty, not covered by Hong Kong distributor warranty. This means the price is usually lower than official Hong Kong stock, but any warranty service during the warranty period must be handled through our store and cannot be taken directly to the distributor's service centre. Please confirm that you accept this arrangement before purchasing; keep the packaging, invoice and warranty card.
What other common questions are there?
Can the HD 600 be driven by a mobile phone?
Do I definitely need a headphone amplifier for 300Ω headphones? How much does an entry-level one cost?
Which is better, the HD 600 or HD 650?
Will open-back headphones leak sound?
What is the difference between parallel imports and official Hong Kong stock?
Sources and Verification Method
Prices were retrieved from DIGIBAL ONLINE's SHOPLINE product API on 2026-10-28. They reflect the lowest configuration price for each model, excluding shipping and promotions; specifications are based on the brand's official pages. This article was compiled by the DIGIBAL ONLINE editorial team. If there is any discrepancy with the product page, the product page and official specifications shall prevail.
